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This star map shows the Houston sky at 10 p.m. CDT on July 1, 9 p.m. CDT on July 15, and dusk on July 31. To use the map, put the direction you are facing at the bottom.The Summer Triangle is high in the east. This consists of the brightest stars in Cygnus, Lyra, and Aquila. Scorpius, the Scorpion, is in the south, with the ‘teapot’ of Sagittarius to his left. Leo, the Lion, sets in the west. From the Big Dipper’s handle, ‘arc to Arcturus’ and ‘speed on to Spica’ in the southwest. Watch Mars close in on Saturn this month.

Saturn is also in the southwest at dusk. This month and next, Mars approaches Saturn more and more.

Venus remains in the morning sky. Look east at dawn for the brightest point of light there; only the Sun and Moon outshine Venus. Venus remains a morning star for almost all of 2014.

Jupiter is behind the Sun and out of sight this month.

The Big Dipper is left of the North Star, with its handle pointing up. From that handle, you can ‘arc to Arcturus’ and then ‘speed on to Spica’; those stars are in the west at dusk. Leo, the Lion, is setting in the west at dusk.

At about 7 p.m. on Thursday, July 3, Earth is as far from the Sun as it will get this year. This is aphelion, when Earth is 94.56 million miles from the Sun, as opposed to the average distance of 93 million miles. On January 4, Earth was at 91.44 million miles from the Sun; that was perihelion (closest approach to the Sun). It turns out that this variation in the Earth-Sun distance is too small to cause much seasonal change. The tilt of Earth’s axis dominates as it orbits the Sun. That’s why we swelter when farther from the Sun and shiver when we’re closer.

This star map shows the Houston sky at 10 p.m. CDT on June 1, 9 p.m. CDT on June 15, and dusk on June 30. To use the map, put the direction you are facing at the bottom. Jupiter sets in the west in Gemini, the Twins. The Big Dipper is as high as it gets in the north. Leo, the Lion, is high in the west at dusk. From the Big Dipper’s handle, arc to Arcturus and then speed on to Spica in the south. Saturn is left of Spica in Libra. Cygnus, Lyra, and Aquila form the Summer Triangle in the east, as Scorpius and Sagittarius rise in the southeast. Summer has arrived.

This month, Jupiter remains in the evening sky for one more month. Look for it low in the west at dusk, outshining all the stars we ever see at night.

Saturn was up all night long last month. Now, it remains well-placed for evening observing. Look low in the southeast at dusk.

Venus remains in the morning sky. Look east at dawn for the brightest point of light there; only the Sun and Moon outshine Venus. Venus remains a morning star for almost all of 2014.

The Big Dipper is above the North Star, with its handle pointing up. From that handle, you can ‘arc to Arcturus’ and then ‘speed on to Spica’; those stars are in the south at dusk. Leo, the Lion, is high in the west at dusk.

At 5:51 a.m. on Saturday, June 21, the Sun is directly overhead at the Tropic of Cancer — the farthest point north where the Sun can be overhead. This therefore marks our summer solstice. On this date, those of us in the northern hemisphere experience the longest day and shortest night of the year, and the midday Sun is as high as possible in the sky. From the Southern Hemisphere, the Sun is as low as possible in the sky on June 21. Folks down there have their shortest day and longest night on their winter solstice.

Interestingly, we see our earliest sunrise on June 11 and latest sunset on July 1. These are not on the solstice because Earth does not orbit the Sun at constant speed. Rather, Earth speeds up a little near perihelion (January) and slows down a little near aphelion (July). Thus, for a period extending 10 days before and after the solstice, both sunrise and sunset occur a little later each day. (This close to the solstice, the difference in the height of the Sun each day changes only imperceptibly, allowing this small secondary effect to dominate). As most of us sleep through sunrise and are awake at sunset, days will seem to lengthen all the way through June.

This star map shows the Houston sky at 9 p.m. CST on March 1, 9 p.m. CDT on March 15, and 8 p.m. on March 31. To use the map, put the direction you are facing at the bottom. Jupiter is high overhead in Gemini, the Twins. Dazzling Orion the Hunter is to the Twins’ lower right. To Orion’s left are the two Dog Stars: little dog Procyon and big dog Sirius. Sirius outshines all other stars we see at night. In the north, the Big Dipper is higher in the sky. Leo, the Lion, rises in the east. These stars, along with Arcturus, announce the coming spring. Mars now rises in late evening.

This month, Jupiter remains well placed for evening observing all winter and spring. Look for it almost overhead at dusk and high in the west later in the evening.

Mars remains in the morning sky. It continues to brighten a bit in the south at dawn. Later in March, it also begins rising in late evening (9:30 p.m. on March 5; 8:20 p.m. on March 31)

Saturn remains in the pre-dawn sky. Face south immediately before sunup to see it.

Venus has now entered the morning sky. Look southeast at dawn for the brightest point of light there; only the Sun and Moon outshine Venus. Venus remains a morning star for almost all of 2014.

Brilliant winter stars shift toward the southwest during March. Dazzling Orion is almost due south at dusk. His three-starred belt is halfway between reddish Betelgeuse and bluish Rigel. Orion’s belt points up to Aldebaran in Taurus the Bull. This winter and spring, the Bull also contains Jupiter. To Orion’s upper left are the twin stars Castor and Pollux, marking the heads of Gemini, the Twins. You can find Sirius, the brightest star we ever see at night, by drawing a line from Orion’s belt towards the horizon. To Orion’s left, about level with Betelgeuse, is Procyon, the Little Dog Star.

From Sirius, look a little bit to the right and then straight down to the horizon. If your southern horizon is clear of clouds and tall earthly obstacles, you’ll see Canopus, the second brightest star ever visible at night. This star is so far south that most Americans never see it, and many star maps made in the USA omit it. (You must be south of 37 degrees north — the latitude of the USA’s Four Corners — for Canopus to rise). As you view Canopus, keep in mind that the sky we see depends on our latitude as well as on time of year and time of night.

Joining the winter stars are stars of spring rising in the east. Look for Leo the Lion at dusk. Later in the evening, extend the Big Dipper’s handle to “Arc to Arcturus” and then “speed on to Spica;” these stars rise at about 10 p.m. in early March, but by 9 p.m. on the March 31.

Sun., Mar. 9, is the second Sunday of the month. Accordingly, Daylight Saving Timebegins at 2 am that morning. (The time goes from 1:59:59 to 3:00:00, with the 2 a.m. hour skipped.) Don’t forget to set your clocks forward one hour!

At 11:57 am on Thurs., Mar. 20, the Sun is directly overhead at the equator. That makes this the vernal equinox, one of two days when everyone on the planet has the same amount of daylight. Many consider this the ‘official’ start of spring. That’s because for us, days have been lengthening, with the Sun slightly higher in the sky each day, from December until now. After March 20, days continue to lengthen, making day longer than night. In the Southern Hemisphere, their long summer days have been shortening until now, with the Sun lower in the sky each day. After March 20, they continue to shorten, making day shorter than night. For them, then, this is the autumnal equinox.

On most clear Saturday nights at the George Observatory, you can hear me do live star tours on the observation deck with a green laser pointer. If you’re there, listen for my announcement.

This star map shows the Houston sky at 9 p.m. CST on Feb. 1, 8 p.m. CST on Feb. 14, and 7 p.m. on Feb. 28. To use the map, put the direction you are facing at the bottom. The Great Square of Pegasus sets in the western sky. Taurus, the Bull, is almost overhead. Dazzling Orion, the Hunter is high in the south, with his two dogs behind him. Sirius, the Big Dog Star, is the brightest star we ever see at night. Jupiter, in Gemini, approaches the zenith on February evenings. Look for Canopus, the second brightest star ever seen at night, low in the south.

This month, Venus has entered the morning sky. Look southeast at dawn for the brightest point of light there; only the Sun and Moon outshine Venus. Venus remains a morning star for almost all of 2014.

Jupiter, up literally all night long last month, remains well placed for evening observing all winter and spring. Look for it in the east at dusk and almost overhead later in the evening.

Mars remains in the morning sky. It continues to brighten a bit in the south at dawn.

Saturn remains in the pre-dawn sky. Face south-southeast right before sunup to see it.

In February, the Big Dipper only partly risen at dusk. Its two pointer stars — the stars farthest from the handle which point at the North Star —may be high enough to see over trees and buildings.

Watch the Great Square of Pegasus set in the west at dusk. Taurus the Bull is high in the south. Look for the Pleiades star cluster above reddish Aldebaran. Dazzling Orion the Hunter takes center stage on winter evenings. Surrounding Orion are the brilliant stars of winter. Orion’s belt points down to Sirius, the Dog Star, which outshines all other stars we ever see at night. The Little Dog Star, Procyon, rises with Sirius and is level with Orion’s shoulder as they swing towards the south. To the upper left of Orion’s shoulder is Gemini, the Twins, which contains Jupiter this winter.

Under Sirius and low to the southern horizon this month is a star that most Americans never get to see: Canopus. Representing the bottom (keel) of the legendary ship Argo, Canopus is the second brightest star ever visible at night (second to Sirius). Thus, it is clearly noticeable along the southern horizon on February and March evenings. However, you must be south of 37 degrees north for Canopus to rise. (This is the line that divides Utah, Colorado, and Kansas from Arizona, New Mexico, and Oklahoma.)

The sky we see depends on our latitude as well as on the time of night and time of year. From any given location in our hemisphere, there is an area of the sky around the North Star in which stars never set (circumpolar stars), and an equivalent area around the South Celestial Pole in which stars never rise. The closer you are to the pole, the larger these areas are. Observers in Canada, for example, have many circumpolar stars, but there is also a large area of stars that they never see. The closer you get to the equator, the fewer circumpolar stars there are, but there are also fewer stars that never rise for you. At the equator, no stars are either circumpolar or never visible; all of them rise and set as Earth turns.

That’s why, down here in south Texas, the Big Dipper sets, although it’s always up for most Americans. On the other hand, Canopus, too far south to rise for most Americans, rises here.

The Moon takes 27.34 days to orbit Earth; one cycle of Moon phases lasts 29.54 days. At 28 days long, February is the only month shorter than a lunar phase cycle, and thus the only month that can have only three of the four main phases. That’s the case this year, as a New Moon occurred at the end of January and the next comes early on March 1.

On most clear Saturday nights at the George Observatory, you can hear me do live star tours on the observation deck with a green laser pointer. If you’re there, listen for my announcement.